Datasheet

+3.3V, 622Mbps SDH/SONET
Laser Driver with Current Monitors and APC
Maxim Integrated 11
MAX3669
TOP VIEW
MAX3669
TQFP
(5mm x 5mm)
32 28
293031
25
26
27
MODSET GND APCSET N.C. BIASMAX N.C. N.C. CAPC
10
13
15
14
1611 12
9
ENABLE
FAIL
GND
N.C. N.C.
V
CC
GND
BIAS
17
18
19
20
21
22
23
MD
24 V
CC
GND
GND
V
CC
OUT-
OUT+
V
CC
2
3
4
5
6
7
8MODMON
BIASMON
V
CC
GND
DATA-
DATA+
++
V
CC
1V
CC
24 23 22 21 20 19
BIASMAX
MODSET
GND APCSET CAPC V
CC
789101112
ENABLE
GND
N.C.
GND
BIAS
13
14
15
16
17
18
V
CC
OUT+
OUT-
V
CC
GND
MD
6
5
4
3
2
1
MODMON
EP
BIASMON
GND
DATA-
DATA+
V
CC
FAIL
THIN QFN
(4mm x 4mm)
MAX3669
At +5V power supply, the headroom voltage for the
MAX3669 is significantly improved. In this case, it is
possible to achieve a modulation current of more than
50mA (using resistor pullups as shown in the Typical
Operating Circuit ). The MAX3669 can also be DC-coupled
to a laser diode when operating at +5V supply; the volt-
age at OUT+ should be ≥ 2.0V for proper operation.
Layout Considerations
To minimize inductance, keep the connections between
the MAX3669 output pins and LD as close as possible.
Optimize the laser diode performance by placing a
bypass capacitor as close as possible to the laser
anode. Use good high-frequency layout techniques
and multilayer boards with uninterrupted ground planes
to minimize EMI and crosstalk.
Laser Safety and IEC 825
Using the MAX3669 laser driver alone does not ensure
that a transmitter design is compliant with IEC 825. The
entire transmitter circuit and component selections must
be considered. Customers must determine the level of
fault tolerance required by their application, recognizing
that Maxim products are not designed or authorized for
use as components in systems intended for surgical
implant into the body, for applications intended to sup-
port or sustain life, or for any other application where the
failure of a Maxim product could create a situation
where personal injury or death may occur.
Pin Configurations